Many technologies exist to detect and quantitate biomolecules, such as DNA, mRNA, proteins, small compounds, etc. However, available assays typically require expensive reagents and/or time consuming labor-intensive steps. For example, polymerase chain reaction (PCR) is a proprietary method which requires the use of an expensive enzyme such as Taq polymerase. Other methods such as chemiluminescence require enzymes and substrates. Methods using fluorescent probes require no enzymes, but are less sensitive than methods using enzymatic reactions.
Furthermore, sensitive assays are usually conducted in a small volume of less than 100 μL, so very small volumes of moderate to highly concentrated biomolecules are needed. Most purification methods result in large volumes of dilute samples which are not appropriate for sensitive assays. In addition, many molecular techniques require a series of enzymatic modifications with purification in between. This can result in continuous dilution and loss of the biomolecules, making the methods inefficient.
Thus, a simple, inexpensive method is needed for concentrating dilute samples of biomolecules, detecting the presence of small amounts of biomolecules in a sample, and analyzing the concentration of biomolecules in a sample. Preferably the method can be used for high-throughput applications.
Disclosed herein is the first systematic assay for sample concentration followed by detection, characterization, and manipulation, simultaneously.